High volume confbridge, what to expect, maybe cluster?


I am wondering what the correct setup for a high volume confbridge would be. Our basic setup is a single Asterisk machine with 4 pri lines (=120 channels) and some voip trunks.

my question I guess is two-fold:

  1. when should I expect to reach the limits of my single machine (dual quad core xeon cpu, 16GB RAM, SAS disks).
    I have options to grow:
  • bigger CPU’s
  • I could extend the machine to the point of supporting up to 2 or more 8 port PRI interfaces 240, 480, or more pri channels. What is the maximum number of PRI cards / ports a single machine can deal with?
  • I could add vitually unlimmited voip channels…

When will I hit the wall of not being able to support more hardware or channels on a single machine?

  1. when I hit this limit, what are my options?
  • can I cluster multiple machines to support one big load of channels
  • should start doing some smart routing? hosting one conference on one machine and another on the next?

Any advise is much appreciated!

Sorry to be pushing this… but any ideas on the matter would be very welcome…!